A battery generally comprises a plurality of battery cells and a battery management system. The battery management system in turn usually comprises a monitoring device that monitors the behavior of the battery cells, and a switching device that ensures that a current flows to and/or from the battery cells only when permitted by the monitoring device. The monitoring device monitors parameters relevant to the correct operation and safety. These parameters also include, for example, the temperature of the battery.
The switching device usually uses semiconductor switching elements, in particular MOSFETs. These have the property that they can operate as switches only in one direction since they can block the flow of current only in one direction. Since, however, blocking is possibly necessary in both directions, those semiconductor switching elements are connected in series in the reverse orientation (anti-series). Both charging currents and discharging currents can therefore be switched off. To ensure a sufficient current-carrying capacity, multiple such arrangements of semiconductor switching elements connected in series are often arranged in a parallel manner.
The known arrangement of the semiconductor switching elements is symmetrical. This means that the same number of semiconductor switching elements is respectively used to block the flow of current in both directions. The semiconductor switching elements used are identical in this case and differ within the switching device only in terms of the direction in which they are connected. In particular, all semiconductor switching elements used have the same dielectric strength. In electronic components such as semiconductor switching elements, the parameter of the dielectric strength is known to indicate the voltage at which the corresponding component can still be operated.
However, known switching devices for a battery management system have disadvantages in terms of costs and efficiency. It could therefore be helpful to provide an electronic switching device for a battery management system, which switching device has increased efficiency while reducing costs.